High efficiency evaporatively cooled condenser

ABSTRACT

The heat exchanger of the present invention provides a plurality of tubes defining refrigerant passages extending vertically from a lower end to an upper end. According to an exemplary embodiment, the refrigerant passages carry superheated refrigerant. A bottom header is in fluid communication with the passage at the lower end of the tube, and a top header is in fluid communication with the passage at the upper end of the tube. A plurality of plates extend rearwardly from the tubes to a distal edge. Adjacent plates extending from adjacent tubes are closed off at the distal edges by a connector, and adjacent plates extending from the same tube have a rear opening between the distal edges for receiving air into the assembly. A plurality of orifices are disposed along the plates to allow air from the rear opening to flow downstream between the tubes. A water tank and wicking material are provided for wetting the plates. The water abstracts heat from air passing over the plates and evaporates into the airstream. The cooled air continues downstream toward the tubes, and receives heat rejected from the superheated refrigerant.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The subject invention relates to conditioning air and, morespecifically, to conditioning air more efficiently using the principlesof evaporative cooling.

2. Description of the Prior Art

It is known to cool air by flowing the air over an evaporator comprisinga set of tubes carrying a refrigerant. The heat is transferred from theair to the refrigerant to cool the air. The refrigerant then passesthrough a compressor and is compressed into a superheated vapor. Theheat must be rejected out of the refrigerant before it can be used tocool additional air. Typically, the heat is rejected into the atmosphereby transferring to ambient air flowing over a condenser comprising a setof tubes carrying the superheated refrigerant vapor. As the refrigerantcools, it condenses back into a liquid. These tubes are referred to ascondensing tubes. However, since this system requires energy, continuingattempts have been made to increase the cooling efficiency and reducethe energy required. One such example is found in U.S. Pat. No.6,354,101 to Levitin et al., which teaches evaporating water from aseries of rods upstream of a condenser. When the air passes over therods, heat is transferred to the water, causing it to evaporate andthereby reducing the temperature of the airstream. The air entering thecondenser is cooler and therefore able to receive more heat from thesuperheated refrigerant, which reduces the energy consumption of the airconditioner. However, the assembly of Levitin is bulky and requires theuse of extra components, such as the rods.

SUMMARY OF THE INVENTION AND ADVANTAGES

The invention provides a tube defining a refrigerant passage extendinglongitudinally from a lower end to an upper end, with a bottom header influidic communication with the passage at the lower end of the tube, anda top header in fluidic communication with the passage at the upper endof the tube. A plate extends longitudinally from a lower end to an upperend and projects outwardly from the tube to a distal edge, and a supplyof water is provided for wetting the plate. The water evaporates fromthe plate and cools air moving over the plate.

BRIEF DESCRIPTION OF THE DRAWINGS

Other advantages of the present invention will be readily appreciated,as the same becomes better understood by reference to the followingdetailed description when considered in connection with the accompanyingdrawings wherein:

FIG. 1 is a front perspective view of a heat exchanger in accordancewith a first embodiment of the present invention;

FIG. 2 is a rear perspective view of the heat exchanger in accordancewith the first embodiment;

FIG. 3 is a top view of the heat exchanger in accordance with the firstembodiment;

FIG. 4 is a front perspective view of a heat exchanger in accordancewith a second embodiment of the present invention;

FIG. 5 is a rear perspective view of the heat exchanger in accordancewith the second embodiment;

FIG. 6 is a top view of the heat exchanger in accordance with the secondembodiment;

FIG. 7 is a front perspective view of a heat exchanger in accordancewith a third embodiment of the present invention;

FIG. 8 is a rear perspective view of the heat exchanger in accordancewith the third embodiment; and

FIG. 9 is a top view of the heat exchanger in accordance with the thirdembodiment.

DETAILED DESCRIPTION OF THE INVENTION

Referring to the Figures, wherein like numerals indicate correspondingparts throughout the several views, a condenser assembly 20 for an airconditioning system is shown generally. The assembly 20 includes aplurality of tubes 22 spaced apart from each other. The tubes 22 extendin a vertical direction from a lower end to an upper end between abottom header 24 and a top header 26. A plurality of dividers 28 extendvertically within each of the tubes 22 to provide a plurality ofrefrigerant passages. The tubes 22 have parallel sides extendinghorizontally between a rounded front and a closed back. A plurality offins 30 extend horizontally between adjacent tubes 22 from the front tothe back and define a downstream section for receiving air between theadjacent tubes 22. A blower 32 is provided to move air through theassembly 20, as is well known in the art. A water tank 34 is provided todefine a supply of water for wetting the tubes 22. The water tank 34surrounds the lower ends of the tubes 22, and a tube-side wickingmaterial 36 extends upwardly from the water tank 34 on the outside ofthe tubes 22. Water moves through the wicking material by capillaryaction into the downstream section. Although the water tank 34 is shownaround the lower ends of the tubes 22, it could also be placed aroundthe upper ends to allow gravity to assist the wicking action.Additionally, two water tanks 34 could be used around the lower andupper ends of the tubes 22.

A plurality of plates 38 each extend rearwardly from each of theparallel sides of each tube to a distal edge. Adjacent plates 38extending from the same tube define an upstream section, and a rearopening is formed between the distal edges of these plates 38. Airprovided by the blower 32 is received in the upstream section via therear opening. The water tank 34 also surrounds the lower ends of theplates 38 about the upstream section, and a plate-side wicking material40 extends upwardly from the water tank 34 to line, i.e. cover, theplate. Water is therefore introduced to the upstream section bycapillary action similar to the water in the downstream section.

A midstream section is defined between adjacent plates 38 extending fromadjacent tubes 22. The midstream section is closed off at the back by aconnector 42 that extends vertically to connect the distal edges ofthese plates 38. Therefore, the midstream section is aligned with and influid communication with the downstream section. The plates 38 include aplurality of orifices 44 to allow air to flow from the upstream sectioninto the midstream section. The fins 30 extend rearwardly from thedownstream section to extend between the plates 38 in the midstreamsection. The fins 30 help direct the air flow from the orifices 44forwardly from the midstream section to the downstream section.

The blower 32 may be operated to move air through the rear opening to beinitially cooled by evaporating water from the plates 38. The air isthen moved through the orifices 44 to the midstream section and into thedownstream section, where it may be further cooled by evaporating waterfrom the tubes 22. According to a first exemplary embodiment,superheated refrigerant enters the tubes 22 and condenses into a liquidby rejecting heat to the cool airstream.

As shown specifically in FIGS. 1-3, the connector 42 is a connectorpanel 42 extending transversely to the plates 38 and connecting thedistal edges of the plates 38. According to a second exemplaryembodiment, shown specifically in FIGS. 4-6, the plates 38 extend fromadjacent tubes 22 and converge toward one another to an apex. Theconnector 42 connects the distal edges at the apex.

According to a third exemplary embodiment, shown specifically in FIGS.7-9, the plates 38 are corrugated to increase the available surface areaand to increase the cooling effect. The plates 38 of the presentembodiment have a continuous “S” shape as viewed in cross sectionextending laterally substantially the entire width of the plates 38.

While the invention has been described with reference to an exemplaryembodiment, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the scope of the invention. Inaddition, many modifications may be made to adapt a particular situationor material to the teachings of the invention without departing from theessential scope thereof. Therefore, it is intended that the inventionnot be limited to the particular embodiment disclosed as the best modecontemplated for carrying out this invention, but that the inventionwill include all embodiments falling within the scope of the appendedclaims.

1. An assembly for conditioning air comprising; a tube defining arefrigerant passage and extending longitudinally from a lower end to anupper end, a bottom header in fluid communication with said passage atsaid lower end of said tube, a top header in fluid communication withsaid passage at said upper end of said tube, a plate extendinglongitudinally from a lower end to an upper end and projecting outwardlyfrom said tube to a distal edge, and a supply of water for wetting saidplate to evaporate the water from said plate and thereby to cool airmoving over said plate.
 2. An assembly as set forth in claim 1 furtherincluding a blower to move air over said plate and over said tube.
 3. Anassembly as set forth in claim 1 wherein said supply of water includes awater tank surrounding at least one end of said plate and a plate-sidewicking material extending from said water tank and lining said platefor moving water by capillary action from said water tank to said plate.4. An assembly as set forth in claim 3 wherein said supply of waterincludes said water tank surrounding said lower end of said tube and atube-side wicking material extending from said water tank and liningsaid tube for moving water by capillary action from said water tank tosaid tube.
 5. An assembly as set forth in claim 4 further including atleast two tubes spaced apart from one another to define a downstreamsection therebetween and at least one of said plates projecting fromeach tube to define a midstream section therebetween aligned with and influid communication with said downstream section.
 6. An assembly as setforth in claim 5 wherein said plates include a plurality of orifices forreceiving air flow into said midstream section and a connector extendinglongitudinally and connecting said distal edges of said platesprojecting from adjacent tubes to define a closed back of said midstreamsection.
 7. An assembly as set forth in claim 6 further including a pairof said plates projecting from each tube to a rear opening between saiddistal edges to define an upstream section between said pair of platesprojecting from the same tube for receiving air flow from said rearopening and for providing air flow to said orifices.
 8. An assembly asset forth in claim 7 wherein said tubes include parallel sides definingsaid downstream section and said plates are aligned with said sides ofsaid tubes.
 9. An assembly as set forth in claim 8 wherein said platesare parallel to one another.
 10. An assembly as set forth in claim 8wherein said connector comprises a connector panel extendingtransversely to said plates and connecting said distal edges of saidplates.
 11. An assembly as set forth in claim 7 wherein said tubesinclude parallel sides defining said downstream section and wherein saidplates projecting from adjacent tubes converge toward one another to anapex and said connector connects said distal edges at said apex.
 12. Anassembly as set forth in claim 7 wherein each of said plates includes atleast one corrugation extending longitudinally therealong in an “S”shape as viewed in cross section.
 13. An assembly as set forth in claim12 wherein said plates further comprise corrugated plates having acontinuous “S” shape corrugation extending longitudinally therealong asviewed in cross section and extending laterally substantially the entirewidth of said plates.
 14. An assembly for conditioning air comprising; aplurality of tubes spaced apart having a closed front and parallel sidesextending vertically from a lower end to an upper end and horizontallyfrom said front to a back, a bottom header in fluid communication withsaid lower ends of said tubes, a top header in fluid communication withsaid upper ends of said tubes, each of said tubes including a pluralityof dividers extending vertically within each of said tubes to define aplurality of refrigerant passages for receiving refrigerant flowingbetween said headers with one of said dividers defining said back ofeach tube, a plurality of fins extending horizontally between adjacenttubes and extending horizontally from said front to said back to definea downstream section for receiving air between said adjacent tubes, ablower arranged to move air into said downstream section, a water tanksurrounding said lower ends of said tubes above said bottom header sothat said tubes extend through said water tank, a tube-side wickingmaterial extending upwardly from said water tank on the outside of saidlower ends of said tubes for moving water by capillary action into saiddownstream section, a plurality of plates each extending vertically froma lower end to an upper end and extending rearwardly from each side ofsaid tubes to a distal edge to define a rear opening between said distaledges of adjacent plates extending from the same tube and to define anupstream section between adjacent plates extending from the same tubefor receiving air flow from said rear opening, said water tank defininga supply of water for wetting said plate and extending rearwardly fromsaid back of said tubes to surround said lower ends of said plates aboutsaid upstream section for open communication between said water tank andsaid upstream section, a plate-side wicking material extending upwardlyfrom said water tank and lining said plate for moving water by capillaryaction from said water tank into said upstream section, a connectorextending vertically and connecting said distal edges of adjacent platesextending from adjacent tubes to define a midstream section therebetweenaligned with and in fluid communication with said downstream section,said plates including a plurality of orifices for air flow from saidupstream section to said midstream section, and said fins extendingrearwardly from said sides of said tubes and extending between saidplates in said midstream section for directing the air flow from saidorifices forwardly from said midstream section to said downstreamsection, whereby the air flow may be moved by said blower through saidrear opening and initially cooled by evaporating water from said platesand then moved through said orifices to said midstream section and intosaid downstream section to be further cooled by evaporating water fromsaid tubes while receiving heat from the refrigerant flowing within saidtubes.
 15. An assembly as set forth in claim 14 wherein said connectorcomprises a connector panel extending transversely to said plates andconnecting said distal edges of said plates.
 16. An assembly as setforth in claim 14 wherein said plates extending from adjacent tubesconverge toward one another to an apex and said connector connects saiddistal edges at said apex.
 17. An assembly as set forth in claim 14wherein each of said plates includes at least one corrugation extendinglongitudinally therealong in an “S” shape as viewed in cross section.18. An assembly as set forth in claim 17 wherein said plates comprisecorrugated plates having a continuous “S” shape corrugation extendinglongitudinally therealong as viewed in cross section and extendinglaterally substantially the entire width of said plates.